1. Field of the Invention
The invention relates to a holding device, more particularly to a holding device for holding an electronic module that is to be tested by a testing apparatus.
2. Description of the Related Art
FIG. 1 illustrates a conventional holding device that includes a pair of opposing walls 211, a clamping unit 22, a pair of electrical connectors 23, and a hydraulic driving unit 24. With further reference to FIG. 2, the conventional holding device serves to hold a dual in-line memory module (DIMM) 1 that is to be tested by a testing apparatus (not shown). The DIMM 1 includes a printed circuit board, a plurality of integrated circuits mounted on the printed circuit board, and a set of contact pins 13 that are disposed along an end of the printed circuit board and that are coupled electrically to the integrated circuits. The walls 211 define an accommodating space 213 therebetween. The end of the printed circuit board is disposed in the accommodating space 213 when the DIMM 1 is held between the walls 211. The clamping unit 22 is disposed in the accommodating space 213, and includes a pair of clamps 221 that are operable so as to clamp the end of the printed circuit board of the DIMM 1.
Each of the electrical connectors 23 has first and second ends, each of which is provided with a set of electrical contacts 232, 233. The first end of each of the electrical connectors 23 is connected detachably to a respective one of the clamps 221 of the clamping unit 22. The electrical contacts 233 on the second end of the electrical connectors 23 are connected electrically to the testing apparatus. The hydraulic driving unit 24 controls the operation of the clamps 221 of the clamping unit 22. As illustrated in FIG. 3, the electrical contacts 232 of each of the electrical connectors 23 are respectively in contact with the contact pins 13 of the DIMM 1 when the clamps 221 of the clamping unit 22 are operated by the hydraulic driving unit 24 to clamp the printed circuit board of the DIMM 1, thereby permitting the testing apparatus to perform tests on the DIMM 1.
Although the aforementioned conventional holding device achieves its intended purpose, the hydraulic driving unit 24 generates undesirable noise. Moreover, since the electrical contacts 232 of the electrical connectors 23 are brought into contact with the contact pins 13 of the DIMM 1 by means of clamping, the first ends of the electrical connectors 23 are easily damaged, thereby requiring frequent replacement of the electrical connectors 23. Further, since the DIMM 1 is subjected to high temperatures during soldering of the integrated circuits on the printed circuit board, deformation of the DIMM 1 occurs. As such, since the clamps 221 of the clamping unit 22 are rigid, the electrical contacts 232 of the electrical connectors 23 may not be properly brought into contact with the contact pins 13 of the deformed DIMM 1, thereby making the test results inaccurate.
In U.S. Pat. No. 6,071,137, there is disclosed a conventional holding device that addresses the above-mentioned problems. The conventional holding device includes opposing first and second walls, a deformable sheet member, a plurality of contact elements, and a force-imparting unit. The first and second walls define an accommodating space for extension of a DIMM thereinto. The deformable sheet member has a first end that is connected to the first wall, and a second end that is opposite to the first end of the deformable sheet member and that is coupled to the first wall through a pivoting member. The contact elements are attached to the deformable sheet member and are coupled electrically to a testing apparatus. The force-imparting unit is mounted on the first wall, is in fluid communication with the accommodating space, and is operable so as to impart a pushing force on the deformable sheet member for elastically deforming the deformable sheet member to a contact position, where the contact elements are respectively brought into contact with the contact pins of the DIMM, thereby permitting the testing apparatus to perform tests on the DIMM.
However, the aforementioned conventional holding device is disadvantageous in that, since the second end of the deformable sheet member is coupled to the first wall through the pivoting member, the deformable sheet member swings along with the pivoting member when the pushing force imparted by the force-imparting unit on the deformable sheet member. As such, the contacts elements may be misaligned with the contact pins of the DIMM, thereby obtaining inaccurate test results. In addition, a high precision is required to manufacture the conventional holding device so as to mitigate the aforesaid misalignment drawback, thereby resulting in relatively high manufacturing costs.